use Indigo\Cart\Cart;
use Indigo\Cart\Item;
use Indigo\Cart\Store;

/* Note: these are interfaces, you cannot instantiate them */

$cart = new Cart;

$cart->addItem(new Item);

// Get total price
$cart->getTotal();

// Get item count (item * quantity)
$cart->getQuantity();

foreach($cart->getItems() as $id => $item) {
    // Get subtotal
    $item->getSubtotal();

    // Get price
    $item->getPrice();

    // Get name
    $item->getName();
}

// Throws an Indigo\Cart\Exception\ItemNotFound
$cart->getItem('non_existent');

$store = new Store;
$store->save($cart);

use Indigo\Cart\Store;

$store = new Store;
$cart = $store->find('cart_id');

// Throws an Indigo\Cart\Exception\CartNotFound
$store->find('non_existent');